1. Field of the Invention
This invention relates to method for fertilizing leguminous plants.
2. Description of the Prior Art
Leguminous plants are characterized by their ability to fix nitrogen microbially from the atmosphere, usually in nodules connected with their root systems, and their ability to use the fixed nitrogen to produce proteinaceous seeds. The commercial products from leguminous plants are, in the main, seeds enclosed in true pods which are generated from the plants' flowers. Less than 10% of the flowers of the plant are normally converted to seed pods. Most flowers are aborted because of the inability of the plant to supply the nutrients required during period of stress when flowers are converted to mature seed pods among other reasons. Legumes constitute some of the world's most important agricultural crops; e.g., peas, beans, soybeans and peanuts.
Recent investigations have reported that foliar feeding of leguminous plants with liquid plant foods, when carefully applied, produces an increase in seed yields. Single or multiple applications of small amounts of aqueous plant foods containing urea, potassium polyphosphate and potassium sulfate have been purported to increase soybean yields significantly. Practical results, however, have been erratic and frequently poor because of foilage burn.
A number of chemical compositions containing water-insoluble nitrogen have been used as soil fertilizers to take advantage of the extended period of nitrogen release for the feeding of the root systems of plants. Some of the chemicals, previously reported for slow release of nitrogen for root fertilization include: isobutyl diurea, melamine, oxamide, urea-formaldehyde polymers, and others. Legume bearing plants fertilized with the foregoing compositions exhibit growth stimulation but improvement in pod production is not significant.